The present invention relates to a new and distinct variety of Buddleja (butterfly bush) grown as an ornamental shrub for home and commercial landscapes. Butterfly bush is typically grown for its attractive, fragrant flowers that are borne throughout the growing season.
The new and distinct variety of butterfly bush resulted from a formal breeding program established by the inventor in Raleigh, N.C., United States. One of the objectives of the breeding program was to develop a dwarf statured, male and female sterile, spreading Buddleja with red-purple (RHS 72C) flowers. ‘Pink Micro Chip’ was selected at a research station in Jackson Springs, N.C. in 2010 from a population of about 150 seedling progeny derived from a hand pollinated cross of ‘Lilac Chip’ (U.S. Plant Pat. No. 24,016)×‘Miss Molly’ made in summer 2009 in Raleigh, N.C. ‘Lilac Chip’ was the female (seed) parent, and ‘Miss Molly’ was the male (pollen) parent in the aforementioned hybridization. ‘Lilac Chip’ is a complex hybrid containing 3 different species and one botanical variety of Buddleja (B. davidii, B. davidii var. nanhoensis, B. lindleyana, and B. globosa). ‘Miss Molly’ was derived from hybridization of ‘Miss Ruby’×‘Attraction’. ‘Miss Ruby’ was derived from hybridization of ‘White Ball’×‘Attraction’. ‘White Ball’ is a complex hybrid, presumably containing B. davidii and B. fallowiana. ‘Attraction’ was derived as an open-pollinated seedling of ‘Honeycomb’, which is a hybrid of B. globosa×B. davidii. NC2000-1 is a hybrid of ‘Nanho Purple’×Buddleja lindleyana. ‘Nanho Purple’ is a variety derived from Buddleja davidii var. nanhoensis. All of the hybridizations described above, with the exception of the development of ‘White Ball’ and ‘Attraction’, were accomplished in the inventor's research program. The complete pedigree of ‘Pink Micro Chip’ is shown in FIG. 4. Of all the parents used in the development of ‘Pink Micro Chip’, the varieties ‘Blue Chip’ (U.S. Plant Pat. No. 19,991), ‘Miss Molly’ (U.S. Plant Pat. No. 23,425), ‘Miss Ruby’ (U.S. Plant Pat. No. 19,950), ‘Attraction’ (not patented), ‘White Ball’ (not patented), ‘Nanho Purple’ (not patented), and ‘Honeycomb’ (not patented), and the species Buddleja lindleyana are available in commerce.
The seeds resulting from the 2009 controlled hybridization process were harvested in fall of 2009 and germinated in a greenhouse in Raleigh, N.C. in the winter of 2010. The resulting 150 seedlings (approximate) were planted in field trials in spring of 2010 at a research station in Jackson Springs, N.C. These plants flowered in summer 2010, and one plant, designated NC2010-22, was selected in July, 2010 for its very dwarf stature, spreading habit, attractive red-purple (RHS 72C) colored flowers, oblong-elliptic leaves, flowers lacking anthers (male sterile), and lack of seed set (female sterile). This original plant demonstrated characteristics identical to those subsequently expressed on other plants when propagated from stem cuttings. This single plant is the subject of the present invention Buddleja ‘Pink Micro Chip’.
The inventor conducted the first asexual propagation of ‘Pink Micro Chip’ in fall 2010 in Raleigh, N.C., and ‘Pink Micro Chip’ has subsequently been propagated in the same location in years 2011 through 2013. In all cases, the original plant selection was propagated asexually by softwood to semi-hardwood stem cuttings. Such cuttings root readily under mist in about 14 to 21 days, and resume normal growth. Four plants derived from stem cuttings of the variety were established in experimental greenhouse trials in Raleigh, N.C. in fall, 2010 and in 2011. Subsequently, ten plants derived from stem cuttings were established in a field trial in Jackson Springs, N.C. in 2013. Through successive asexual propagations, the characteristics of the original plant have been maintained. Thus, plants derived from stem cuttings exhibit characteristics identical to those of the original plant, and no aberrant phenotypes have appeared.
Test plantings and performance evaluation over four years at a research station in Jackson Springs, N.C. and a greenhouse in Raleigh, N.C. demonstrate this variety to be relatively consistent in its characteristics even under the different growing conditions associated with yearly climatic variation.
Plants of the new variety are very dwarf after establishment in the field, being less vigorous and more dwarf than most cultivars of butterfly bush available in commerce. Young plants have averaged about 38 cm of height growth per year. Plants are spreading in growth habit. Flowering occurs in the first year of growth on newly formed wood. The inflorescence is a panicle, and shows a light red-purple flower color. Flowering usually begins in late May to early June in Jackson Springs, N.C., and continues throughout the growing season until the first freeze event in October or November. An individual inflorescence flowers for about 7-10 days, depending on temperature, but new flowers are made during the entire growing season. Flowers are essentially female sterile, and the new cultivar has set no seed to date in greenhouse or field trials, even under conditions of intentional controlled pollination, an asset in landscape plantings.
‘Pink Micro Chip’ is distinguished from other related known cultivars based on the unique combination of traits including very dwarf plant size, dense spreading growth habit, green leaves (RHS 137C) with oblong-elliptic shape, attractive red-purple (RHS 72C) flower color, lack of anthers (male sterility), and female structures that are essentially sterile. “Essentially sterile” is used because applicant does not preclude the possibility that seed set may be observed on rare occasions. The cultural requirements for ‘Pink Micro Chip’ are well-drained soil, full sun, and moderate moisture. ‘Pink Micro Chip’ exhibits no serious pest or disease problems known to the inventors, except for occasional spider mite infestation during periods of hot, dry weather.